Whilst watching Glesga physics presentation on nuclear physics I came across this nasty but interesting little application, nukemap. You choose a location, select a nuclear bomb and blow it up. Gives a very good idea of the devastation caused by nuclear weapons. I tried dropping a "little boy" on the centre of the town village very small village  in Flekke. I had thought that my house would have been destroyed but in fact it wasn't (marked by the arrow). It would be interesting to see peoples perceptions of magnitude of destruction caused by a nuclear weapon. The biggest weapon ever produced, the "Tsar Bomba" would not only vaporised our house but would destroy the whole kommune.

Here's what Valdo has to say about E=mc² and nuclear physics.